Answer
$AC$ = $25$ $in.^2$
$CB$ = $144$ $in.^2$
$BA$ = $169$ $in.^2$
Work Step by Step
All we are asked to do is square each of the sides. Remember to square the units as well:
First side:
$AC$ = $($5$ in.)^2$
Square both the value and the unit:
$AC$ = $25$ $in.^2$
Second side:
$CB$ = $($12$ in.)^2$
Square both the value and the unit:
$CB$ = $144$ $in.^2$
Third side:
$BA$ = $($13$ in.)^2$
Square both the value and the unit:
$BA$ = $169$ $in.^2$